Steering linkage



Feb. 23, 1932. H. 1.. HIRSCHLER STEERING LINKAGE Filed Aug. 5; 1929 4Sheets-Sheet l INVENTOR. Horace A .fl/k'jc/l/zr i. 8 0? {a AJNEYZ.

Feb. 23, 1932. H. LIHIRSCHLER 1,346,553

STEERING LINKAGE Filed Aug. 5, 1929 f 4 Sheets-Sheet; 5

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Feb. 23, 1932. I H. L. HIRSCHLER 1,846,553

STEERING LINKAGE Filed Aug. 5, 1929 4 Sheets-Sheet 4 INVENTOR. fi oracz L Mrsc/r/zr A TTORNEYS.

vPatented Feb. 23, 1932 srnnnme LINKAGE Application filed August 5, 1929; Serial No. 388,510. My invention relates steering vehicles and is cerned with the steering to mechanism for matic, showing the forward portion of a vehi particularly conclc provided with the steering linkage of my arrangement on a invention. multi-Wheeled vehicle of the type disclosed Fig. 2 is an elevation looking in the direca in Patent N o. 1 721,732, issued July 23, 1929, tlon of the arrow in Fig. 1. p

to Charles A. Ifawkins and in the copending Fig. 3 is a side elevation, somewhat diaapplication of Hawkins, Hirschler and Lothrop, Serial N 0. 382,972, filed August 2, 1929, and entitled Vehicle. Such multihicle. wheel vehicles usually comprise six, eight or Fig. 4 1s a motion study of the linkage of more ground engaging wheels most of which my invention associated wlth the left-hand are subject to steering or dirigible movement. wh t- Diiiiculty has been experienced in providing F g. 5 1s a motion study of the linkage of a suitable steering linkage which will eifect my invention associated with the right-hand the proper dirigible movement of each of the Wheels. wheels for all of the various different radii of In its preferred form, the steering linkage turning of the vehicle. It is relatively a simof my nventi n comprises a frame on e ther ple matter to calculate mathematically the ide of which at least a pan of tandem dirvarious different angles for each of the wheels igible wheels is located and which is profor the different turning radii of any given ended with a cross shaft, actuated by a steervehicle but it is a distinctly involved problem mg gear, and l to design a steering linkage which will effect stub shafts and suitable linkage to the mthe desired movement. This result has heredividual dirlgible wheels for pivoting them tofore been approached by the use of cams ab steering axes in the mathematior cam surfaces in some form or other but cally correct amount to effect the proper these mechanical expedients are difficult to cation of the wheels for all of the various radii of turning of the vehicle in both directions.

manufacture, maintain and operate and inv crease the cost of a vehicle more than is or- Although the steering linkage of my 1nvention is capable of embodiment in numerdinarily desired.

It is therefore an object of my invention to ous difl'erent envlromnents and is capable of considerable variation within the scope of provide a steering linkage which is effective to steer the vehic e properly'for all different the invention, I have chosen to show it herein as, it is applied to the type of vehicle shown radii of turning.

Another object of my invention is to proin the above mentioned patent and in the vide a simple linkage for effecting this result. above mentioned application. This vehicle A further object of my invention is to proincludes eight wheels engaging and pivotally attached to a frame vide a linkage, omitting the use of cams, for

upwardly and downwardly in a vertical effecting the proper steering of a multiwheeled vehicle. plane. Some of these wheels are also mounted An additional object of my invention is to to pivot about a steering axis which is apuse a number of duplicate parts in the linkproximately vertical or is slightly inclined age so that the cost thereof is kept at a low to the vertical. For clarity in description I have herein disclosed only the forward porand reasonable figure.

A still further object of my invention is to tion of such a vehicle but it will be obvious to those skilled in the art that my linkage 45 facilitate the manufacture of the steering can as well be applied to other portions of portion of a multi-wheeled vehicle. The foregoing and other objects are ata vehicle or can be extended to include more than four wheels.

tained in the embodiment of the invention The vehicle preferably includes a frameshown in the drawings, in which work 6 comprising a pair ,of parallel longias installed on the forward portion of a vethe ground for motion grammatic, of the linkage of my invention 1 Fig. 1 is a plan View, somewhat diagramtudinal side rails 7 and 8. The side rail 7 is assumed to be on the right hand side of the vehicle while the side rail 8 is on the left hand side of the vehicle; Adjacent the side rail 7 is a pair of dirigible wheels 9 and 11 arranged in tandem and adapted to pivot about steering axes 12 and 13. These axes are slightly inclined to the vertical to improve the steering characteristics. On the left hand side of the vehicle adjacent the frame rail 8 is a second pair of wheels 14 and 16 likewise arranged in tandem and adapted to pivot for dirigible movement about steering axes 17 and 18 inclined in the same manner as the axes 12 and 13 but with reverse symmetry with respect thereto. The mounting of the wheels on the frame 6 forms no part of the present invention and it is understood that any suitable type of mounting can be utilized, preferably one such as is shown in the patent and application above mentioned.

In order to effect the proper steering of the various wheels enumerated I preferably provide a steering gear 19 suitably mounted on the framework 6 and preferably attached to the side rail 8. This steering gear can be of any conventional type and in the present instance includes a housing 21 containing gearing capable of imparting rotary motion to a cross shaft 22 upon corresponding rotary motion of a steering rod 23 under control of the vehicle operator.

The cross shaft 22 extends transversely of the vehicle and of the frame 6 and is suitably mounted in journals 24 and 26 fastened on the side rails 7 and 8. Arranged to be actuated by the cross shaft 22 are two similar sets of subsidiary linkages. The linkage for the right hand wheels 9 and 11 preferably ineludes a pair of levers 27 and 28. For convenience in construction these levers are usually incorporated in one unit, as-shown in Figs. 1 and 2, which, at one end is suitably mounted on the cross shaft by a clamp 29. Projecting from the unit is a pin 31 located at a predetermined angular relationship with the axis of cross shaft 22 while projecting similarly is a pin 32 at a predetermined angular relationship to the pin 31 and to the axis of shaft 22.

In longitudinal alignment with pin 31 is a similar pin 33 at the radial extremity of a crank arm 34. This crank arm is affixed to a stub shaft 36 extending transversely of the frame 6 and disposed parallel to the cross shaft 22. The crank arm 34 is disposed in a predetermined angular relationship with the crank arm 28 and the two pins 31 and 33 are moved simultaneously by virtue of a link 37 which is journalled at opposite ends to the respective pins 31 and 33. Similarly. a link 38 connects the pin 32 with a pin 39 forming part of a crank arm 41 in turn fixed on a stub shaft 42 parallel to stub shaft 36. It will be noted by reference to the figures that the angular relationship of the crank arm 41 with respect to the lever 27 is different than the relationship of crank arm 34 with respect to its comparable lever 28. The net result of the linkage as thus far described is to impart different degrees of angular rotation to the stub shafts 36 and 42 for a predetermined angular rotation of the cross shaft 22.

At the outer extremity of stub shaft 36 I preferably provide a crank 43 which at one end carries a ball 44 connected to a link 46 in turn extending to a connection, as at 47, with a steering arm 48 associated with wheel 9. Thus angular rotation of crank 43 in a substantially vertical plane effects a consequent angular rotation of the steering arm 48 in a substantially horizontal plane. In a similar manner, stub shaft 42 is provided at its outer extremity with a crank 51 carrying at one end a ball 52 connected by a suitable link 53 with the extremity 54 of a steering arm 56 associated with wheel 11. The angirlar relationship of the various cranks and steering arms is such that the varying angular rotation of stub shafts 36 and 42 effects the desired pivotal movement of wheels 9 and 11 about their dirigible axes 12 and 13 in the proper amount for correct location of the wheels for all radii of turning.

In a somewhat comparable manner I provide a subsidiary linkage for operating the wheels 14 and 16 for steering movement. At the left hand side of the frame adjacent side rail 8 levers 61 and 62 are preferaably affixed to the cross shaft 22 by a clamp 63. It may be noted that for economy in manufacture levers 61 and 62 are identical with levers 27 and 28 but project from the cross shaft 22 in substantially the opposite direction and are disposed with reverse symmetry. Lever 61 is provided with a pin 64 connected to a link 65 which, at its opposite end, is fastened to a crank arm 66 on a stub shaft 67. Similarly lever 62 is provided with a in 68 engaging a link 69 extending forwar ly to a connection, shaft 73. Stub shafts 67 and 73 are preferably in axial alignment with stub shafts 36 and 42 and likewise extend transversely of the frame and parallel to cross shaft 22. It will be observed, however, that crank arms 66 and 72 bear different angular relationships to their respective axes than do the crank arms 34 and 41.

At the outer extremity of stub shaft 67 I afiix a crank 74 at its radial extremity provided with a ball 76 engaging a link 77 also connected, as at 78, to a steering arm 79 associated with wheel 16. In a comparable manner stub shaft 73 is at its outer end provided with a crank 81 carrying a ball 82 for connecting with a link 84. This link at its forward endconnects, as at 86, with a steering arm 87 associated with wheel 14. The anguas at 71, with a crank arm 72 on a stub lar relationship existing between cranks 81 and 74 and steering arms 87 and 79 is such that the proper degree of pivotal movement is given to wheels 14 and 16 to locatethe wheels in the proper positions for all radii of turning of the vehicle.

It will be appreciated that upon a given. angular movement of the steering rod 23 which effects an exactly corresponding anguw lar movement of cross shaft 22, all of the Wheels in the unit described are given their proper locations for steering at all of the varlous radii of turning both to the right and to the left by virtue of the varying anguw lar relationships and varying directions of the several cranks and crank arms and levers. It will be further appreciated that in accordance with my invention the linkage is composed of a number of substantially iden- 2e tical partswhich reduce thecost of manufacture and that no cams are necessary although the results achieved aremathemati cally exact.

It is to be understood that I do not limit 25 myself to the form of steering linkage shown and described herein, as the invention, as set forth in the following claims may be em bodied ina plurality of forms.

I claim:

'1. A steerin linka e comprising a frame, a pair of tan em dirigible wheels mounted on said frame, a steering arm for each of said wheels, a pair of stub shafts arranged transversely on said frame, a crank on each of said stub shafts, a link connecting each of said steering arms to said cranks, a cross shaft on said frame, a steering gear for rotating said cross shaft, a pair of levers on said cross shaft, a crank arm on each of said stub shafts,

L and a link connecting each of said levers to said crank arms. i 2. A steerin linkage. comprising a frame, a pair of tan em dirlgible wheels mounted on said frame, a parallel pair of tandem dirigible wheels mounted on said frame, a steering arm for each of said wheels, a pair of stub shafts arranged transversely at one side of said frame, a second pair of stub shafts arranged transversely at the other side of said frame, a crank on each of said stub shafts, a link connecting each of said steering arms to said cranks, a cross shaft on said frame a steering r for rotating said cross shaft, a pair of evers at one end .55 of said cross shaft, a crank arm on each of said first-named stub shafts, a link connecting each of said levers to said crank arms, a pair of levers at the other end of said cross shaft, a crank arm on each of said secondnamed stub shafts, and a link connecting each of said second-named levers to said secondnamed crank arms.

In testimony whereof, I have hereunto set my hand.

HORACE L. HIRSCHLER. 

